Not with permissive parents who are more keen to not be in opposition to their children in any capacity obvs.
It certainly did with my parents. No way in hell I'd have even mentioned the word boyfriend in any serious capacity at 15 let alone bring one to the house. I'm not grateful for much, but certainly grateful for that.
Yeah I know in the super progressive philosophy today, it's seen as guided facilitation is better than prevention, but that's from a place of parental disempowerment frankly.
If anyone can put forth the case for how beneficial it is for a girl to be facilitated in having underage sex at 15 with a jobless, emotionally incapable, underage schoolboy, whose still living in his parents home, pays no bills, is incapable of providing for any children (or paying for a private abortion if necessary) and has no respect for his daughters parents and their house at all, or any self control (the OPs daughter admitted she didn't intend to do that) and whose likely to be boosting about his sexual prowess/methodology to his mates, please tell me. In fact why should a boy in such a position expect sex at all?
I'd personally be having a frank conversation and telling my daughter that with her youth and beauty in a couple years she could do a hell of a lot better if she's feeling hot and wants to have sex. I would tell my daughter about her sexual power. She would not be wasting herself on schoolboys who can barely afford McDonald's let alone unexpected children. And her first time should be special, not some furtive grab in some schoolboys sweaty bedroom while his parents are out!
Encouraging boyfriends and precocious dating is to put sex on the agenda. With internet, PG 12 films and virtually almost no watershed anymore, we no longer live in that innocent age where girls and boys just hold hands and a first kiss is a BIG deal at 18-21 even. And frankly a lot of first time sex at such a young age is closer to coercion than consent.
But I agree it's too late to turn back now when things have reached this point. Nothing the parents can do now after that silly decision but to talk practicalities which part the OP has done well.
I think we live in an age where people still have low expectations of girls, it's still there in the background. To be clear, sex at this age may benefit boys far more than it benefits girls. The boys get social alpha status from having sex with no responsibility, never have to take hormones and at best walk away with a weak CM claim in a worst case scenario. Girls? None of that.